1. Field of the Invention
This invention relates to a hypodermic syringe and more particularly to a hypodermic syringe having a protective device to prevent users of the syringe from being inadvertently scratched or cut by contaminated needles.
2. Description of the Prior Art
Health care personnel are frequently encountering the hazard of being pricked or otherwise inadvertently scratched or cut by contaminated hypodermic needles. The health care personnel are at risk in both blood drawing and medicine injection procedures. The patient from whom the blood is drawn or medicine is administered may have infectious agents, such as the hepatitis virus or the human immunodeficiency virus, in his blood. If so, accidental contact between the contaminated needle and the health care personnel may transmit diseases such as hepatitis or AIDS from the patient to the health care worker.
Various devices have been proposed for use, or otherwise used, in the past to cover the needle portion of a hypodermic syringe. Some of these devices leave the needle exposed for a short time after removal from the patient. After this short time, a protective cover is extended over the needle to prevent inadvertent contact therewith. However, such devices do not eliminate the risk that the health care personnel can be struck by the needle immediately upon removal from the patient. Consequently, such prior art devices do not prevent the potentially hazardous, inadvertent contact with the needle of the hypodermic syringe.
Other devices which have been proposed for use do prevent contact with the contaminated hypodermic needle upon removal from the patient, but are very clumsy and awkward to use. One example of such a device is a hypodermic syringe having a spring-loaded covering sheath in which the needle is maintained in a retracted position. The sheath is first provided along the patient's body and the hypodermic syringe is extended through the sheath in such a manner that the needle is inserted into the patient. Upon removal of the needle from the patient, the hypodermic syringe is again retracted into the sheath and the sheath is removed from contact with the patient's body. Such a device is awkward to use because the initial contact between the device and the patient is the cover sheath and not the needle of the hypodermic syringe. Such a device prevents the health care personnel from getting a true "feel" of the area in which the needle is to be inserted. Such a "feel" is especially necessary when the procedure being performed by the health care personnel is the drawing of blood and the location of the needle insertion is of prime importance.
Other safety devices which are adapted to cover the needle immediately upon removal from the patient are difficult to operate and require the use of two hands. Typical of such devices are frictionally sliding cover sheaths on hypodermic syringes and sheaths which are secured to the syringe by threads and require that the sheath be rotated relative to the hypodermic body. Such devices require the use of both hands of the health care personnel, thereby preventing the health care personnel from attending to the patient with his or her spare hand. Moreover, such devices do not cover the needle in the event that the syringe is accidentally dropped. There remains a need for a syringe device which eliminates exposure of an operator to a contaminated needle but affords the operator the freedom of using his or her spare hand to attend to the patient.